RESEARCH WORK.

Auckland Star, Volume LXVIII, Issue 146, 22 June 1937, Page 18

RESEARCH WORK.

VENTILATION SYSTEMS.

PROGRESS IN AMERICA.

AIR-CONDITIONED CARS,

(By EDWARD W. MORRISON.)

DETROIT, April 17

The approach of summer has focused attention ill the automobile world on the efforts of engineers and accessory manufacturers to produce an air conditioning unit that will be suitable for the passenger car. The manufacturers declare that «o much time is occupied in the automobile <luring the summer months that, if it is desirable to cool factories, office buildings restaurants and recreation centres, it must be equally important to add air-conditioning equipment to the automobile. _ ' Many obstacles have been encountered; however, in the search for the right kind of cooling system. In the first place, any acceptable article must not be too expensive—preferably n<?t more than

£14 or £15—since in the beginning it | must occupy the status of extra equip-' ineiit. In the second place, some effn must be u>ade to provide a dual fundi for an air-conditioning unit.- It shon ultimately serve, the engineers say, n.> only to cool the car in summer, but to warm the interior in the winter. Price Not a Seal Difficulty. The engineers are not baffled so much about turning our a device-thpt.-will be priced within a suitable' range '* 8 they are in seeking to adapt recognised aircooling principles to the peculiar Confines of the automobile. They do not-bave nstationary object to work Wifch.'fbr one thing; even the mere ventilating of » movable Object, such as an automobile, presents a complex puzzle. Consider, also, the 'actual applications of lieut that are put ona, motor car in summer weather. Whin'"'temperatures roach 95, 100- and 105, att they have for long stretches of days in the last few summers, the automobile in the sun absorbs enough Ite&t to wreck the refrigerating plans of the most astute workman. - If cars are to be equipped with cooling equipment, some co-operation must be provided by the body- builders, quite a few of the engineers assert. /Either the steel top will have to'be' abandoned or the roof of the car will have to be insulated much better than it is . now. Why heat the car with the sun, the Engineers ask, while at the same time =yo!» are trying to cool it off from within? Most of the air-conditioning models thut have been under study include some kind of fan to propel the cool air. Since all the windows in the.car must be kept, dosed for effective operation .<jf ; i* cooling unit, the;action ol jdoefc! not solve the prqblem; the distribution of the cool air, without undue drafts*? and the elimination of tobacco smoke and accumulated impure air are also problems of importance. Patents have been issued on one model that, in the opinion of some observers, Ims much merit. It meets the need for compactness, in .that it occupies scarcely more than a cubic foot, of room. It can be installed uiider the ; dashboard in the same way a heater is installed. Employed in a small room, scarcely larger than an automobile, it is capable of reducing the mercury 60 degrees in about .15 minutes. • *" " Without well-regulated distribution of the cool air thus produced, the equipment is only partly efficient, however. To provide air ducts through the interior of the car to carry the cool air might easily make the cost of air-condi-tioning equipment prohibitive except for the limousine owner. s Already in Larger Vehicles. One big company is building an alrconditiouiug unit for motor coaches. The fMoblem here has been by no meant* »o difficult, because of the larger area involved. Filtered, cooled and deiiumidiflcd. the air is changed _ completely once evei;'y three minutes.' ' Out"--ide air. brought in-and coojed.-by/£be . "nit. passes through ducts built, into, the lingave racks directly above the seats. The air is forced downward front these compartments to a horizontal mwh'■oom deflector whi( h circulates it in -itch a way as to envelop the passenrrs indirectly, without the discomfprtj cold drafts, 5 UThe outside airy-in, t|»e v /ase of tlii*; t, enters at the* f ronlTof J 'the coach;-* is conveyed the air-conditioning in the rear 1 'isjitttroduced the interior. Power for both the ' erivot compressor and the fan for

air circulation its provided through belt I drives from an independent gasoline engine. On the conventional bus the air is brought in above the windshield, tests having revealed that the outside air is most free from traffic fumes at that point. The air is then diverted downward through a duct at the left of the driver and thence to the blower fan. The outlet of used air is through a static exhaust louvre at the curvature of the front of the roof. Passenger Car System. In the passenger car equipment the fresh air is brought in at the. same point, but is screened and carried through an intake pan installed above the front compartment between headlining and roof. Overhead grills, extending sidewise, in front and rear compartments of the sedan, provide distribution of the fresh air a<s it ie,driven back through the intake pan. Two other grills draw the used air through sealed ducts to the exhaust vent .in the roof.

Tests have disclosed that a complete change of air occurs every minute with the car travelling ten miles an hour. The change is more rapid at higher speeds. The volume of air i« regulated by manual control.—N.A.N.A.